Implements MCU-specific GPIO input interrupt integration. Added
definition of System configuration controller as well as its needed by
the GPIO code.
The SYSCFG controller is used for system-specific configuration such as:
- remap the type of memory accessible at address 0x00000000
- manage the external interrupt line connection to GPIOs
- configure the I/O compensation cell
Change-Id: Id2ebfbd1b21e77be76406d1cd6cd5d4989e9e2fa
Signed-off-by: Ricardo Salveti <ricardo.salveti@linaro.org>
Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
